The remote web server is missing an Apache HTTP Server patch update.
The version of Apache HTTP Server 2.4 installed on the remote host is prior to 2.4.12. It is, therefore, affected by a NULL pointer dereference flaw in module 'mod_cache'. A remote attacker, using an empty HTTP Content-Type header, can exploit this vulnerability to crash a caching forward proxy configuration, resulting in a denial of service if using a threaded MPM.
Upgrade to Apache HTTP Server version 2.4.12 or later.